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Although extreme weather conditions were relatively rare in 1996 - and it was a quiet year in terms of flooding - the notable climatic volatility of the last decade continued. The intense drought experienced during the summer of 1995 heralded the development of a very protracted rainfall deficiency which by the end of 1996, had produced significant concern for the water resources outlook. Through the year the focus of the drought, which extended over 20 months by December 1996, shifted from north-west England to the English lowlands.

The 1996 rainfall total for the UK was 940 mm - 86% of the 1961-90 average and ranking tenth driest this century. Scotland, where rainfall over the ten years beginning in 1986, was around 15% above average, recorded only its second year with below average rainfall since 1978. On a nationwide basis, the June-September period was especially dry, the second driest (over that timespan) in more than 80 years. Fortunately, in a water resources context, 1996 was also the coolest year since 1987 and evaporative demands were generally lower than those which have typified much of the recent past. This helped to moderate water demand and, despite very modest rainfall through the early summer, there was no repetition of the water resources stress of the previous year. Nonetheless, the June-August period added to the recent cluster of dry summers and the autumn recovery in runoff and aquifer recharge rates was patchy and, in most regions, weak. New minimum annual runoff totals were registered at around 20% of the gauging stations in the national network and, by year-end, both river flows and, in particular, groundwater levels were depressed over wide areas.

The relatively dry summer of 1996 and the associated depressed river flows, together with the large soil moisture deficits which were maintained well into the autumn in the lowlands, is consistent with a number of favoured climate change scenarios. However, the limited 1995/96 winter rainfall and the dry cold early winter of 1996/97 emphasise the variability of winters over the last decade rather than reinforcing the recent tendency for winters to be considerably milder and wetter than average. The natural variability of the UK climate is such that any apparent short term trends need to be treated with considerable caution. Nonetheless, the river flow and aquifer recharge conditions experienced since the mid-1980s have been characterised by very wide and protracted departures from the seasonal average. Initial analyses of rainfall and evaporation data, together with evidence from the relatively few hydrometric series extending over 50 years, suggest that there is no close modern parallels to the recent past.